I've written a simple linux program to grab the current system time and display it on an LED display. The time needs to be accurate as the clock is used to count down to an hourly news service via Satellite. We currently have 2 MSF radio clocks and I've now installed these two digital displays. The machine this runs on has a cron task to syncronise the time with a local GPS locked time server. When I started the app the clocks were in sync, after a day the digital clocks have drifted back by a second, this is unacceptable.

My question is, does a process remain synced to the real time clock? I know in Windows 16 bit apps run in a VM which has it's own RTC which I've witnessed go out of sync with the 32 bit clock. Could something similar happen in linux?